Answer to Question #4518 Submitted to "Ask the Experts"

I started having upper right abdominal pains in January and was admitted to the emergency room with abdominal pain and severe headaches. The emergency room physician referred me for a head CT scan and an abdominal CT scan with contrast, which were completed. In March, an abdominal x-ray exam was performed. Also, in March, a CT scan was performed on my esophagus and abdomen to rule out any perforation following an endoscopic exam.

My gastrointestinal doctor stated that he does not know what to do as my extensive blood work, all tests mentioned above, and various gastrointestinal procedures do not indicate what the cause of my abdominal pain is. He has referred me for a GI barium procedure which involves swallowing barium and taking CT scans over four to six hours. Additionally, he mentioned that I might not have any problem, but can all of this testing cause radiation poisoning? This has disturbed me as I want to find out if these exams will result in an overexposure to x rays and increase my risk of radiation poisoning or problems. Should I go ahead with the new test or not? Will additional radiation exposures increase my risks in a negative way?

The term "radiation poisoning" is usually associated with an acute, high radiation dose that results in a rapid onset of symptoms that include a suppression of white blood cells, nausea, etc. I can assure you that such responses are virtually impossible to occur due to diagnostic x-ray examinations.

The principal concerns surrounding medical radiation exposures are associated with the future risk of cancers. However, to properly evaluate your risk, output measurements for the x-ray equipment used would have to be made. Lacking this information, some estimates can be made based on typical diagnostic examinations (http://hps.org/hpspublications/articles/dosesfrommedicalradiation.html). Based on one head CT (200 mrem), one abdominal CT with contrast (approximately 1,000 mrem), one abdominal CT fluoroscopy exam of the chest and abdomen (totaling approximately 1,800 mrem), and one abdominal x-ray exam (70 mrem), your total dose is approximately 3,070 mrem. Taking into account the proposed CT barium swallow and follow-through that might add another 1,000 mrem, your total dose for all these exams should still not exceed 10,000 mrem. There have been no demonstrated effects of exposures of less than 10,000 mrem, or 10 rem (http://hps.org/documents/radiationrisk.pdf). Personally, I do not believe that these exams have significantly increased any future health or cancer risks beyond those that you would expect to encounter if you had not received these exams.

It should be made clear that any decisions as to whether or not you should have further tests have to be made by you with input from your physicians. If necessary, you may want to get a second medical opinion.

John P. Jacobus, MS
Certified Health Physicist